Fa — The Key's Inner Pins¶
One-line pitch: Fa is the struct that holds the cryptographic state of a single SHA token — 13 fields of pure math. Data shape — you don't touch it.
What this is¶
Every SHA has one Fa inside it. Fa stores the values that define this specific key's cryptographic identity: Base, Secret, Signal, Channel, Pole, Charge, Chin, Monopole, and a few more. Think of it as the circuit board of a SHA token.
Fa isn't a contract. It's a struct — a data shape that SHA (and the math library) read and write during reactions.
If you've played a web3 game before¶
- Closest analogy: a private-key's internal state — the raw math that makes the key unique.
- Or: EIP-2335 keystore internals — the encrypted blob that underpins a signing key.
- Or: the pin-height array inside a combination lock.
| Dysnomia term | What it maps to |
|---|---|
| Fa | The 13-field state struct of a SHA |
| Base / Secret / Signal | Seed values |
| Channel / Pole / Charge | Derived during reactions |
| Monopole | Final state after Saturate() |
What you actually do with it¶
- Nothing. Fa is read/written by the math library during SHA reactions.
Rewards / costs¶
- Cost: none.
- Reward: none — it's internal.
Requirements & gating¶
- None for players.
Where it connects¶
Lives inside SHA. Used by the atropaMath library. Its final Charge and Chin values bubble up through reactions into XIE.
Quick FAQ¶
Q: Why so many fields? A: The cryptographic protocol Dysnomia uses has many intermediate values. Each field stores one stage of the computation.
Q: Is Fa secret? A: Some fields (like Secret) should not be exposed. SHA's interface keeps the sensitive parts internal.
Want the Solidity? The contract reference lives at
technical/docs/include/FA.md.